Numerous studies have documented efficacy of vegetated buffer strips (VBS) in removing herbicides from surface runoff. Little is known about the fate of herbicides after deposition in buffer strip soil. Soil samples (0‐ to 2‐cm depth) were collected from a buffer strip and an adjacent bare field (BF). Soil organic C was two‐fold higher in VBS than in BF, and VBS soil maintained about 0.7 log(10) greater propagule density of total fungi and bacteria and 2 log(10) greater gram‐negative bacteria and fluorescent pseudomonads. Corresponding with enhanced microbial populations, VBS exhibited higher endogenous levels of alkaline phosphatase, tetrazolium chloride dehydrogenase, aryl acylamidase, and fluorescein diacetate hydrolytic activity (1.6‐ to 3.8‐fold greater than BF). Batch studies of metolachlor[2‐chloro‐N‐(2‐ethyl‐6‐methyphenyl)‐N‐(2‐methoxy‐1‐methylethyl)acetamide] sorption showed greater capacity to sorb metolachlor in VBS soil than in BF (Kd 2.25 vs. 1.60 mL g−1). Soil treated with 14C metolachlor (1.25 mg kg−1) was incubated for 46 d in a laboratory study. Limited mineralization (<4%) was observed for both VBS and BF. Less 14C (43%) was extracted from VBS samples 46 d after treatment. Extractable fractions consisted primarily of metolachlor, although increasing amounts of polar (e.g., sulfonic acid) and nonpolar metabolites were recovered over time, especially in VBS. Metolachlor half‐life was 10 and 23 d for soils from VBS and BF, respectively, attributed to higher levels of organic matter and microbial activity in VBS soils. Data suggest retention and enhanced degradation of metolachlor as it passes through VBS strips may limit further transport.

Candida albicans is the primary etiologic agent of candidiasis, a disease that can vary from superficial mucosal lesions to life-threatening systemic or disseminated diseases. Strains of C. albicans have been reported to possess long, thin filamentous protein cell surface appendages termed fimbriae (R. B. Gardiner, M. Canton, and A. W. Day, Bot. Gaz. 143:534-541, 1982). These fimbriae were isolated, purified, and partially characterized. The major structural subunit of the fimbriae is a glycoprotein which consists of 80 to 85% carbohydrate (consisting primarily of D-mannose) and 10 to 15% protein. The molecular weight of the glycosylated fimbrial subunit is approximately 66,000, while unglycosylated protein has an approximate molecular weight of 8,644. The fimbriae function as adhesins mediating C. albicans binding to human buccal epithelial cells. Amino acid analysis of the purified fimbrial subunit indicates that the fimbrial subunit is composed of 50% hydrophobic amino acid residues. The N terminus of the fimbrial subunit is blocked to N-terminal sequencing.

Tripartite interactions among Paenibacillus lentimorbus NRRL B-30488 (B-30488), Piriformospora indica DSM 11827 (DSM 11827) and their consortia (B-30488:DSM 11827:: 1:1) with native rhizobial population in the rhizosphere of Cicer arietinum L. (Chick pea) was tested for enhancing nodulations and plant growth promotion. Number of nodules and dry weight per plant significantly enhanced (P = 0.05), which is further evident by N, P, and K uptake by plants and were found to be maximum in B-30488 treated followed by B-30488: DSM 11827 and DSM 11827, as compared with uninoculated control, in 60 days grown chickpea plants. Microbial community structure in the rhizosphere of the four treatments was assessed, using Biolog Eco and MT plates. Principal component analysis (PCA) of carbon source utilization pattern on Biolog Eco plates did not show any clustering among the four samples indicating that in case of individually DSM 11827 and B-30488 treated chickpea rhizosphere there was significant change in microbial community structure, compared with lesser changes in uninoculated and B-30488 and DSM 11827 consortium treated chickpea rhizosphere microflora. Additional carbon sources tested using Biolog MT plates, higher activity of lignin, chitin, and cellulose utilizing microbial communities in the rhizosphere being stimulated by root exudates treated with B-30488 alone or in consortia with DSM 11827, and, in turn, should encourage beneficial symbiotic or mutualistic microorganisms that can act as plant growth promoting and biocontrol agents.

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